Question

which substance is a compound? hydrogen gold oxygen water

Explanation:

A compound is a substance formed when two or more elements are chemically bonded together. Hydrogen (\(H_2\)), gold (\(Au\)), and oxygen (\(O_2\)) are elements (pure substances with only one type of atom). Water (\(H_2O\)) is made of hydrogen and oxygen atoms chemically combined.

Answer:

water